lightfast

adjective

light·​fast ˈlīt-ˌfast How to pronounce lightfast (audio)
: resistant to light and especially to sunlight
especially : colorfast to light
lightfastness
ˈlīt-ˌfas(t)-nəs How to pronounce lightfast (audio)
noun

Word History

First Known Use

1904, in the meaning defined above

Time Traveler
The first known use of lightfast was in 1904

Dictionary Entries Near lightfast

lightface

lightfast

light field artillery

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Cite this Entry

“Lightfast.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lightfast. Accessed 22 Dec. 2024.

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